Acne is a very common problem causing the formation of pimples on the face, neck, back or chest. It varies in type and severity, from light break outs with black and white dots, to heavy cystic breakouts. It is usually accepted that acne mainly affects young people during puberty, but in reality the problem can affect people from all age groups and cause scarring and self-esteem problems. The condition is caused by a blockage in the hair follicles of the skin due to a high sebum production, an oily substance, which hydrates the skin and hair. Sebum mixes with dead skin cells and causes a blockage in the hair follicle, which causes it to bubble up, causing white spots. If the follicle is open towards the skin, the created spot will be black. In more serious cases, the pimples can become infected by the natural bacteria of the skin, causing papules, pustules, knots or cysts. The high levels of testosterone are another reason for teenage acne – fat-secreting glands react to the hormone by producing more sebum. Other reasons for acne can be genetic, and the condition can also be caused by medication, cosmetics, or dietary habits.